Doctors and nurses treating soldiers injured in Afghanistan have begun speaking of a new "signature wound" - two legs blown off at the knee or higher, accompanied by damage to the genitals and pelvic injuries requiring at least a temporary colostomy.

Twice as many U.S. soldiers wounded in battle last year required limb amputations than in either of the two previous years. Three times as many lost more than one limb, and nearly three times as many suffered severe wounds to their genitals. In most cases, the limbs are severed in the field when a soldier steps on a buried mine.

The increase in both rate and number of such wounds is most likely a result of the troop surge in Afghanistan that began last spring, combined with a counterinsurgency strategy that emphasizes foot patrols in villages and on farm compounds. It was noticed by military surgeons in Afghanistan last fall and quantified in late December by a team of surgeons at Landstuhl Regional Medical Center in Germany, where virtually every evacuated soldier stops en route to the United States.

"I've seen these types of injuries before. What I haven't seen is them coming in over and over and over again," said John B. Holcomb, a trauma surgeon at the University of Texas at Houston and retired Army colonel who helped identify the trend.

The report prepared by Holcomb and two surgeons at Landstuhl has circulated at the highest levels of civilian and military command in the past two months. An abbreviated version was provided to The Washington Post with Pentagon permission.

It shows that from 2009 to 2010, the proportion of war casualties arriving at Landstuhl who had had a limb amputated rose to 11 percent from 7 percent - a 60 percent increase. The fraction suffering genitourinary (GU) injuries increased to 9.1 percent from 4.8 percent - a 90 percent increase.

The actual number of patients with the injuries increased even more drastically.

In 2009, 75 soldiers underwent amputation and 21 lost more than one limb. In 2010, 171 soldiers had amputations and 65 lost more than one limb. GU injuries increased from 52 to 142 over the same period.

Month-by-month totals were not provided, but numerous people who have seen the full report say that multiple-limb amputations rose especially steeply starting in September. Lt. Col. Paul Pasquina, a physician who heads the amputee program at Walter Reed Army Medical Center, recently confirmed that those injuries had "gone up a lot." Also on the increase are patients requiring "hip disarticulation" - the removal of the entire thigh bone, which makes fitting and using a prosthesis more difficult.

Injuries to the genitals

Of the 142 soldiers with genitourinary wounds who arrived at Landstuhl last year, 40 percent - 58 men in all - suffered injury to the testicles. Of that group, 47 had injury to one testicle, and 21 men lost a testicle. Eleven soldiers had injuries to both testicles, and eight lost both testicles.

Body armor, which has greatly reduced fatalities, usually includes a triangular flap that protects the groin from projectiles coming from the front. It does not protect the area between the legs from an upward blast. Various laboratories are reportedly working on shielding that would provide such protection.

Although the U.S. Army Medical Command released the data on genital injuries, military officials are reluctant to discuss these wounds further.